Art of electric welding



ART OF ELECTRIC WELDING Filed Feb. l0, 1925 Y '1,544,119k A. R. BRADEN 4 Patented July 7, 1925 untrue STATES LBERC R. BRADEN, 0F BEVERLY, MASSACHUSETTS, AFSSGNGR T NEW JERSEY.

ART OF ELECTRC WELDING.

Application filed February 10, 1923. Serial Fo. 618,499.

To all' whom it 97mg/ concern.'

Be it known that I, ALBERT R. Brianna?, a citizen of the United States, residing at Beverly, in the county of Essex and State of Massachusetts, have 'invented certain 11nn proveniente in the Art of Electric vlWelding,

of which the following description, in con-4 nection with the accompanying drawings, is a specication, like reference characters on il? the drawings indicating like parts in the several' i'igures l This invention relates to methods of and apparatus for Welding together Various objects, especially for the purpose of securing l5 a projecting member upon a. body. An in-l stance of Worlrto which my invention is particularly applicable is furnished in the manufacture of clicking dies carrying stab.- bloclrs, or those projections 4from the inner W side of the die upon which are mounted members :tor periorating or marking the pieces of material cut. ln attaching these blocks to the die-Walls, it has been customary to solder them together; but this does not u furnish as strong a union as is desirable, and

causes the blocks to be detached when the die is heated for the purpose of repair. This invention utilizes electric Welding to effect a strong attachment of the blocks to the a0 dies and in a manner not aected by heat.

The internal, transverse knives of clicking dies may also be attached effectively i-n the same general manner as are the stabblocks.

An object of this inventionv is to avoid 35 overheating of the pieces to be joined, parla ing the cutting; edge. To this end, I localize the heat applied to soften the pieces to be joined, as by limitingn the flow of heating current to an area closely adjacent to the surfaces to be welded. In operating upon 45 clickingr dies, for example, the body of the die is preferably supported upon a non-con ducting surface, While the Welding current passes through the stab-block which is to be attached, and through the body of the die 5i? immediately surrounding the point of contact of the block with it. Pressure is at' the saine time exerted to force the pieces tc gether.

In Welding stab-blocks or other objects of relatively small dimensions, the copper clamping members, ordinarily employed to hold in place such articles upon electric Welding machines, when correspondingly r^- duced, would quickly become too much deformed, by the pressure applied While by the current flowing through them, to be eecti've. Iron clamping` inenibers for such= purposes tend to Weld to the Stoch when heated. It is further ai objectin ention to furnish au eticicnt clamping de? ce by insulating the clamping member 'from the terminals which are to apply the Welding current and thus preventing its flow through said member. rlhe latter is kept below Welding heat and may be of a metal surliciently resistive to deformation to permit it to be ci the desired reduced die mansions.

Other objects. will appear in connection with the following description, illustrated by the accompanying drawinc' which, represents one of the ernhodimen Ich a@ paratus of this invention may assume. 'in thin drawing, A

Fig. l shows, in perspective, the more esn sential portions of the apparatus;

Fig. 2 is a like ric-u or that part ci' the apparatus directly cooperating with Wei-pieces Fig. 3 similarly illustrates these Mts after the Welding has been accomplished, while Fig. 4 shows, in section, a completed Weld.

In carrying ont my improved method, the body-'portion of the Work, appearing in the drawing as a clicking die D, is placed upon the upper supporting Surface o a table l0, this tablebeing fixed upon a befhpicce or frame l2, from which it is electrically insu .lated at 14. Spaced from the table l2 upon the frame, and similarly insulated at 16, is a table i8 mounted upon carriage 2G er ranged to slide upon Wa 1s 22. To bring' th elements to be Welded into Contact and ever upon tlieni the pressure which will enec' their union, the 'table 18 is moved upon its ways toward and from the table l0, this be ing, in. the prese instance, enecreu br s i '1- L, lever fuicrurce on the ile i no lill) wia screw 38A 'member.

'frame-arm 42.

Both the tables may be hollow, to allow them to be cooled by water supplied through pipes '30. Each of the tables, which are conveniently made of iron, is provided with a worlrengaging terminal of an electric circuit. The table l0 is recessed at its inner edge to receive a block 32, this having an upper projection 34 serving as a support for the stabblock'B or other l'object which is to be at l tached to the body D of the die. The upper supporting surface of the projection 34 is of a form generally corresponding to the face of the stab-block which is to rest upon it. The table 18 carries, in.horizontal alinement withl the projection 34, a block or pressure member 36, which is of somewhat greater height than the projection 34, preferably ap roaching the height ofthe die-stock. It may besecured-.Zin place vupon the table by passing through it and being threaded into the table. The stock from vwhich clicking dies are made is wedgeshaped in transversesection, and during the weldin operation is preferably supported upon t e table 10 with its wider or pressurereceiving edge in contact with thc supporting surface. This presents, to thepressure member 36, a side wall of the die which is inclined upwardly and outwardly from such The pressure-surface 40 of the Vmember 36 is inclined to correspond to the die-wall, so that it not only insures substantially continuous contact -to give a proper "ath for the welding current, but also overangs the die, and, when exerting pressure upon it, gives a certain component of force downward, this being eliective to retain the die -against displacement from the table. The blocks 32 and 36 are preferably of copper, since this metal will not weld to, the steelofrthe die and stab-blocksi` The man- .ner inl which they are applied tol the tables permits them to be renewed. readily when they become deformed-'by the sure. j Fixed upon the frame andextending over the tables is an arm or bridge-piece 42, which is shown as insulated romthe frame,

andtherefore fromthe current-terminals, at

44.' Mounted to slide vertically in the arm above the projection 34 is a clamping member in the form of a bar 46, which maybe rectangular in cross-sefction- This bar, at its `upper extremity, is articulated lby links 48 to a horizontal arm 50 pivot-ed upon the The area of the lower or contact-end of the clamping bar is not substantially diferent from vthat of the opposed surface of the stab-block with which it is to Contact, preferably being somewhat smaller,

so that it will not interfere with the'positioning of this block upon its support. The bar 46 I prefer to be of iron or steel, so that, in spite'of its relatively small transverse dimensions, its form will net easily be heat and presconncd to the place lchanged by the heat tc which it is subjected and the pressure which it applies., Fulcrurned uponthe arm 42, above the pivcteda'rm 50, is a lever o2, formed at the end of its Short arm with a cam-face 54 movable inl contact with the upper edge ofthe arm 50. Normally, this arm 50 is raised by a helical .spring 56 interposed between it and the rame-portion 42, this lifting the bar 46 away -from the stabbloclr-supnort 34. Upon swinging the lever 52 toward the front of the apparatus, the'cam-face 54 presses 'i against'a stab-block carried upon the support to clamp this for the welding operation. For this clamping position, the form of the cam-surface is such that the arm is locked, it being released only by movement of the down the pivote-d arm and brings the har 46 lever by the operator in the opposite direcdtion, or rearwardly.

Connected to the tables are 'thefterminals f of the secondary circuit 58 of a .transformer 60, the primary circuit 6l if which is joined vv to some suitable source of electric energy (not shown) and controlled by a switch 62. The transformer is so wound that the cur- 'rent in the secondary circuit will be of comparatively low voltage and great volume, to 1 properly heat the contacting surfaces through which it flows. p

ln welding a stab-block B upon the die D, there is preferably formed upon the latter, at the point at which the block is to be attached, a polished area. fl lto facilitate the weldingoperation. The stab-block has,

at the end which is to be joined to the dieiuu wall, a reduced portion l), 'which is shown l' as of pyramidal contour, the apex being turned toward the wall of the die when the block is laid upon the projection 34,y and' clamped by the bar 46. Thedie is placed upon the table l0 before .the application of the stabebloclr to itsvsupport, it surrounding the block and being separated from the table by asheet 64 of electrical insulating material which is resistive to heat, such, 'for example, as asbestos. The table 18 is now moved inwardly to bring the wall 40 ofV the pressure-block 36. against the. outer wall of the die opposite the point b of the stabblock, and the switch 62of the primary circuit is closed to cause a flow of current through the contacting areas of the ob jects. This, it'will be observed, is almost lentirely limited to that portion of the die are heated by the erted by the member 36 so forces the die- 1 lthe die-stock an lproduces no protuberance upon the opposite side. .After the welding of the block to the die, there maybe mounted in the former the rforating orciitting member P of any desired form.

` Having described my invention, what I claim as new and desire to secure by Letters Patent of the United States is:

1. The method of securing a projecting member u on a body, which consists in supporting tiie body upon a non-conducting surface, pressing the member and body together, and passing welding current through the member and through a portion of the Vbody limited to that adjacent to thel point i' of contact of the member with the body.

vio

2. The method of securing stab-blocks upon clicking dies, which consists in suporting a die upon a non-conducting surace, fixing the block against movement, pressing the die against the block, and passing welding current through the block and through a-portion of the die limited to that adjacent to the point of contact of the block with the die.

3. The method o f securing a stab-block upon a clicking die, which consists in forming the Ibloclr with a point, supportingtlie block in fixed position, carrying the die into contact with the point. of the block passing current through the die and block to. soften them, and pressing the die against the block to cause the point to enter the die and be welded thereto. A

4. The method pf securing a stab-block upon va clicking dic, which consists in fixing the block in place upon a conducting element, placing the .die about the fixed block but insulated from the conducting element, moving a second conducting element against the dic to press it into contact with the block, and passing welding current through the conducting elements, the die and the block While such pressure is exerted.

5. In a welding apparatus, av support, a clamping member co-operating with the support and insulated therefrom, a member arranged to exert pressure upon an object clamped upon the support, said clamping member being insulated from 'the support and pressure member, and means an 6. In a welding apparatus, a table arranged to support a work-portion to be wel ed, from w ich table is a projection for supporting a work-portion, insulating material interposed between the table and the work-portion thereon, a clamping member co-operating with the projection, and a member arranged to press the work-portion upon the table a ainst that supported upon the rojection, t e projection and pressure mem r serving as terminals for the application of the welding current.

7. In a welding apparatus, a table arra ed to sup ort a work-portion to be wel ed, from w ich table is a projection for supporting a work-portion, insulating material interposed between the table and the work-portion thereon, a clamping member co-operating with the projection, and a member arranged to press the work-portion upon the table a ainst that supported upon the rejection, t e projection and pressure mem r serving as terminals for the application of welding current and the clamping maelisnber being insulated from such termin upon clicking dies, a table upon which the pressure-receivin surface of a die may rest, a clamping mem er for holding the stabblock, a ressure member having a contact face inclined upwardly to overhang the inclined face oft e die, and means for appl ing' welding current to the die andsta block.

9. In an ap aratus for welding stab block, the clamping member being insulated.

lfrom the applied current.

10. In an apparatus for welding stabblocks upon clicking dies, means for supporting and applying welding current and pressure' to a die and stab-block, a frameportionl extending over the supportingv means, a clamping bar mounted to move in the frame-portion, and a cam-lever acting upon the clamping bar to actuate said bar and lock it in its clamping relation. In testimony whereof I have signed my name to this specification.

- ALBERT R. BRADEN. v

8.. In an apparatus for welding stab-blocks 

